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Lecture 09. Reactions of Carboxylic Acids, Esters, Amides, & Nitriles.

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today were really in the heart of the chemistry of the carboxyl like dancers family last time after talking in sort of generalities
about their chemistry we introduced the most reactive members of the carboxyl against family reintroduced acid and hide rides and we introduced acid chlorides and we talked about their chemistry today we're going to focus on all of the remaining members of the family will talk about some of the chemistry of carboxyl like acids that we haven't seen before I
will talk about the chemistry of pastors who will talk about it and made a nice trails and these
are all less reactive than acid chlorides and non-hydro itself I wanted to make some generalizations here's a generic gestures structure is a generic carboxyl like tested structure in the hands of what I would say is in general these structures are less reactive these functional groups are less reactive to nuclear files banana Cincinnatus as chloride the ministers chloride in and hydrologists let's say in so they let me make a start with an example that shows a similar type of
reactivity but it's a much less of great degree about
reactivity let's look at the reaction of the simple Western I think for a two-day for all of our examples I'm going to be giving very small In simple compound just because we're going to be riding out a lot of structures so let's take a look at the simple chapel simplest typical Esther Mathilde acetate and the reason I say typical Lester is mates are a little different formic acid although it's the carboxyl like acid is a little more reactive but ascertained said propionate and various other acids kind of the same and let's take ammonia now we're talking about nuclear files before we talked about species like ammonia and hydroxide as basic nucleophile these art super basic nuclear files like green yard reagents and hydride reagents but they're not things that are based only in name and ammonia isn't good enough nucleophile that it will react with esters and so we undergo a reaction to get a set of mind and the other product of the reaction is methanol so we call this reaction and ammo analysis Lysacek
cleavage by ammonia we've already mentioned the term hydrolysis cleavage by water now what I really wanted to be a band trying to to keep everything simple
up here what I really wanted to drive drop here was in an analysis of these names don't matter a whole heck of a lot and have analysis would be within a meeting like all our with it's a general structure of Oran aged 2 or even a secondary meaning over the much less reactive so there's a primary means but also his and some trying to keep all of our drawing simple today also you an animal analysis instead of in an analysis and a mechanism for this I'm not going to ride it out in gory detail because you've seen all of the principles With acid chlorides and hide drives the ammonia is a nucleophile and has a lone pair of electrons on it it could attack the carbon yield even know the carbon of 80 of an Esther is not nearly as Elektra fell like the Carver meal of and hydride or chloride that has good electron withdrawing group pulling away electron density it can attack we expelled math oxide we transfer Proton if you want more detail you can see you textbook for a mechanism for this
reaction but the general GS is that the Carbondale of Anastas group is sufficiently Elektra fell like to react with a basic
nucleophile like the moment were later on also you hydroxide now for all intents and purposes the electoral felicity of the carbon EO Group of an acid is really very similar to an Astor but there's 1 big big difference it's a carboxyl like acid has an acidic Proton so where whereas the 1st thing that happens when you mix and Esther with ammonia is that the ammonia attacks the Carbondale is not a fast reaction
it'll occur over hours of time this is the reaction of Windex when you clean fingerprints
off of the window because Greece the whales in your skin art esters of glycerol they're trying Astor's you've heard of tribalist arrives the index has ammonia and that ammonia is cleaving the Astor groups to break them down into smaller pieces fatty acid and and glycerol so that's an omen all animal analysis now given by comparison I tank as he answered and I mix it with ammonia you might think well it's going to be very similar but as soon I guess it is 1 thing that's very different than methyl acetate it's gotten acidic Proton so nexus cedar gazetted and ammonia you didn't assault you get ammonium acetate but but but but but but but but but for the most part you don't get mad and now I say for the
most part because under the right conditions if you he cried Out of ammonium acetate if you heat the cried out of acidic acid and ammonia and high temperature you
will eventually get some a set of mine out of this is not 8 where I would say useful reactionary reaction that synthetic chemists would typically used to make an animated but you will get some but the 1st thing that will happen and the thing that would
happen under typical conditions would be solved formation not and the formation
of a new can you about how you're getting ahead of a I'd make the alcohol group regretted leaving group by approximating gets the answer is yes said sit tight years Pirates so we are learning talked about the concept of PKA and we talked about the concept of PKA specific the lady of the conjugate answered we said that the of the conjugate acid of ammonia or the conjugate acid of been Amin was about 10 or 11 and that's a typical sort of moderately basic compound kind of the same PKS Hydro Sianna and cyanide another species that as you just encountered on the quiz is a reasonably good nucleophile now by
contrast if you go to something like water then you have something that's much less basic much less nucleophilic the PKK of the hydrodynamic of the conjugate asset of
water is negative 1 . 7 water is very weakly basic duties basic but sort of in name only so as I mentioned in there our previous discussion of Astor's if I just Nixon Nestor and water you have no reaction and I also mention that that's fortunate for you because all of the leopards in your body all of your cell membranes are made up of esters and so if they cleaved at
37 degrees Celsius if they underwent
hydrolysis at any appreciable rate you'd be you'd be in trouble now bye it's similar to open again and using the velocity values in a lot today just because it's a nice example and then I'll use seated guests sort of in a set of mind sort of his counter points but of course these
could be any asters and any assets sold
by very similar token defined Nicklaus methanol and the CTK again the Carbondale is moderately Elektra felt like former and Astor it's moderately Elektra like former and
acid but water and alcohols are very weak
basis and very weak nuclear and remember when we're standing over PKK is and I'm tossing out numbers like negative to two-word negative story for the PKK of the conjugate asset of an alcohol or negative 1 . 7 4 water and positive 10 Werner Lorant stamped no the words were standing over 12 orders of magnitude What is that tender the 3rd is a thousand million billion trillion the waters of difference in basis city a trillion orders of magnitude EPA trillion times different reactivity to a first-order approximation as nuclear Felicity tracks with basis that if a reaction of ammonia and my philosophy tape takes a minute roughly then your ballpark it they're going to say a trillion minutes for the reaction of water and methyl acetate EUR trillion minutes for the reaction of methodologies cedar guessing why don't know about you I don't know for me I don't expect to be around EUR trillion minutes from now so they're not going to react to our rights and our reaction fire so chemists love to make stuff happen they love to make what they want to have happen happen and so if you want a seat against said to react with methanol as was alluded earlier you do something that can coordinate the carbon group that's going to make the carbon he'll group like a trillion times more electoral fell at another words you probably made it in the presence of a very strong innocent so I could write that if I take a seat gas said and I mix it with methanol in the presence of method of sulfuric acid I get methyl acetate can I get a molecule of water removed any promises I keep repeating ovaries bad balancing equations but it's really important to keep this in mind because this reaction is an equilibrium and so if I go ahead and just mix them and dull
have a lot of methanol just a little bit of methanol only have an equilibrium in the water and methanol for all intents and purposes similar I have a lot of methanol or gotta do something to
soak up the water and sulfuric acid actually really likes water so that's 1 of the ways to make it hang on to to to drive the reaction is just to use more than a little hint of sulfuric acid question but was the H 2 SO 4 he is indeed a catalyst I'm technically you don't need to use a whole mole equivalent in practice sulfuric acid or often is used in a reasonable quantity for exactly the reason I said because it had tends to bind to the water it helps drive the reaction as well but it's not consumed by the reaction so in fact chemist when they write a reaction like this will often shows solvent and reagents within an hour and so you'll often see this written and sulfuric acid sometimes you'll see a written as a catalyst Nunavut parenthesis cat and often you'll see methanol just indicated it's the solvent now with the city gas that I might use as little as possible but if I have a valuable carboxyl like Gaston I'm probably going to use a whole big splash of methanol a whole part of methanol hold last fall of methanol for
a couple of grams of acid and so here's a product of the reaction now this reaction has been known for
a long time it was discovered or invented by fishermen so it's called the fisheries verification sometimes people will use sulfuric acid for the reaction sometimes values another strong mineral lasted like hydrochloric acid ironically in the laboratory if I want to I'm hydrochloric acid In methanol not more water so I don't want go to a bottle in the laboratory in the stockroom and get HCL with water in it 1 of the ways of doing that 1 of the ways of debt and hydrous ACL and methanol is to throws a mess until chloride into my methanol it'll react to give and methanol and methyl acetate and those all will be just the methyl acetate I might not pay attention to and then I might use this as a reaction to take a big valuable carboxyl like tested and make America Lester out of it so this is often how we're all was alive with the far-right let's take a look at the mechanism of the reaction so on acid times go on and off all different lone pairs in England parents weekly is going to get protonated it's an equilibrium throat sulfuric acid a strong acid into methanol if so disassociated approach makes the methanol to my strongest asset in methanol is protonated methanol as a leveling effect you learned about in general chemistry so protons collide protons come of when the Carbondale gets carbonated the Carbondale goes from being moderately Elektra fell like to being very Alexis de like we shall the flow of electrons by joining the Kerberos from the electrons to the hydrogen representing the formation of a new font electrons flow back on to the oxygen atom we have an equilibrium regenerate the probe aided acidic acid plus methanol the but my electrons and not always good about writing my lone pairs but I'll put my lone pair of electrons back
onto the oxygen where they belong now this
process the population of the Carbondale has made it into a good electrified now it's ready to react even with a relatively weak nucleophile like methanol electrons flow from the lone parent methanol To the cardio carbon atoms we start to form a bond but concurrently because we can't have elected 10 electrons around the carbon concurrently electrons flow up on To the oxygen atoms I didn't know OH group here we get it's a myth that Citigroup the protons and a positive charge on it in another OH group and I will try to be as good as I can about keeping track of all of my lone pairs of electrons so we form detector he'd
roll intermediate standard strong acid protons go on protons come protons go
on and off every lone pair of electrons and so all you can think of it as a proton being directly transferred among their I probably think of this more is being mediated by solvent I'd say that's a better way to think about the process and so in our equilibrium but we have lots and lots of methanol around protons flow on protons fall off I will draw the Kerberos representing the flow of electrons back to the methanol but but but but but but but but but but but but but but but but but it doesn't matter which side I write this Proton on its side I write the lone pair of electrons on I'm representing a centrifugal oxygen atom an oxygen atom with force substituent equally disposed about it I guess she told a regional program at all for the geometry of the accident right so that so that sort of takes us to an uncharged data he'd rolling media and this looks a heck of a lot like a gentle dialog with you think about it in the common theme in all of this chemistry that we've talked about is these types of territory he'd roll intermediates these types of German dials are not generally stable at the end of last lecture at the end when we were talking about acid talents on a previous lecture him I Os
Italcementi glucose as site like the example that was stable will see a territory here all intermediate that's stable in the discussion section where you actually have it
as a low-energy species like Dean General Chetta roll intermediates are not stable there not something that you can isolate report Nevada there just a high-energy species as stable stable enough that it's in an energy well stable enough that it can sit around for a microsecond but not stable enough that you could put it in a bottle and so our reaction continues in strong acid proved times come on protons of we put a proton back on the Met thought group would just on backwards pathway and soon going to continue foward with protons come on and off office every lone pair of electrons this so now we've protonated whatever all age groups doesn't matter which 1 gets protonated they're both equivalent remember were just after he wrote about this oxygen now just as we had the attack we can have a break down and now with the expulsion and water electrons flow down from the oxygen we can't stop at that point because that would force us to have 10 electrons around carbon hardened can't accommodate 10 electrons and so we're going to break down actually I'm going to good person and write this mechanism on different lines to give me a moment here understand continue the balance here and so I will write the breakdown of this territory Negro intermediate in the next authorities so as I was saying electrons flow down from the oxygen they field the back onto the oxygen of this gives us the molecule although the protonated methyl ester and we have expelled from molecules of water In the final step is the very reverse of the 1st step of the reaction in the 1st
step in put a proton onto a in the last step we take a proton off of a protonated Carbondale
we're in this vast sea of methanol remember this is an equilibrium reaction if we don't have a lot of excess methanol you're going to get only partial conversion to the yesterday so we have a ton of methanol floating around and and all of which impregnated forces served as the catalyst is now going to accept the prime time of protonated methanol at the very 1st step but the reaction was consumed arrested catalyst was consumed in the very last step is regenerated and so those those 6 steps constitute the mechanism for our fisheries verification may constitute the mechanism for Esther for Munster questions so that our yes really you go along you have to think of it in the past which set in the light of the house yeah that on top of it up so your
question is what is it program made this oxygen why is this oxygen promenade along the lines of the war I did not want right there yeah why is this protonated because when we push electrons down Over here it ends up with a positive charge on the oxygen now remember in the back of your mind when you see this structure as we just on the quiet as there are multiple contributing residents forms so that is 1 residents for in your mind for a 2nd about 2 other residents form you can picture and other residents form in which the positive charges on this carbon and the 3rd resonance chopped form in which we have a double bond to this oxygen single bond to this oxygen and a positive charge on this oxygen and collectively all 3 of those
resonance structures make up a picture of the actual species just as in Iraq so being a mile on I asked you to draw 1 structural always fine if you drew 2 residents structures war it was flying as a matter of fact if you draw any of the 3 resonance struck many of the 2 residents structures so we're just thinking about 1 of the the different pictures that are present in part because if you look at this it's already long mechanism and so you're sort of holding in the back of your head all of this relevant stuff alright any other questions that I wanted to talk about the reverse reactions the hydrolysis investors remember Pfisterer certification as an equilibrium so it might take and again I'm keeping my whole lecture Really Really Simple with several small molecules if I take methyl acetate and I treated it now with water and sulfuric acid I'm going behind realize that too acidic gasses and .period methanol just the reverse of the reaction I could write it like this I should write it for the life here saying I'm treating it with sulfuric acid in water it's all the same thing from the ANC since this game is so identical to what we just saw off at this point you should be able to write a mechanism for acid catalyzed Esther hydrolysis only then to you the but but but but but but it's identical to the mechanism that I just rode up but in reverse and you can figure that out alright no 1
will want to look at about the chemistry of investors carboxyl like acids and then talk about and needs in 93 also then
again now the fire keep things plan is simple and general esters has a set of moderately Elektra felt like they react with strong nuclear files by trade Nestor with sodium hydroxide potassium hydroxide for most intensive purposes these are equivalent in water I get the carboxyl assault get the alcohol we call reactions of pontifications the reaction that mankind has been doing for hundreds of years before we had organic chemistry the making of salt when you take a fat which is a try Astor of glycerol 1 2 3 propane try all with 3 long chain carboxyl against it as terrified on and you stir it with sodium hydroxide that's why Torino the sodium hydroxide hide relies is set on a the glycerol esters to get the sodium salts of the carboxyl that have greasy tales and Paula had groups and white both water in Greece which is very good for getting clean in the shower makes myself so reaction here saying saying principle as we saw Nam analysis I kind of wanted them when I was talking about this and thinking about where the presented I kind of wanted to presented after we did the water the acid promoted hydrolysis but mechanistic lady it's right up there with the am analysis and an analysis we talked about in other words are as group hydroxide is a strong is a good base in moderately strong faces relatively strong base to good enough nuclear file it attacks are Carbondale of give you a little bit of an abbreviated mechanism here only showing relevant lone pairs we get Arteta architecture he girl intermediate is going to breakdown it kicks out the OR group and again I'm just skipping a few long Paris here this gives rise to to the carboxyl against it was the Alcock side In the elk oxide is
basic and so the outcome oxide reacts to warm the carboxyl late and again I'm not going to lie down and every curved arrow in every step in painful detail but
the carboxyl late reacts to give you the outcome oxide salt that's the out to give you the the Alcock side reacts to give you the carboxyl at stalled In the alcohol and in a prosperous lives since if I carry out this reaction in the laboratory and I want to isolate might carboxyl like acid a very common laboratory procedure to set a master with sodium hydroxide then washed the 8 layer that contains the carboxyl late salt to remove the alcohol and any on reacted Esther to extract it with the 3rd to watch over the 3rd and then very commonly In the laboratory will a with some strong acid in water like BCL arranged USO 4 and isolate from their the carboxyl like said sometimes the laboratory it will precipitate out all right so that gives us a little bit of an overview of carboxyl like nonsense In and Out masters and now I want to move onto the last members of the last remaining members there are plenty of other members in the carboxyl like innocent family but I wanna move onto the last main members of the family on Ammons and nite tree also am it's all right them in general foreman was 2 are groups fear that the 2 hydrogen is in which case we have a primary and middle hydrogen our group which case we have a secondary damages our groups in which case we have the tertiary nite look very different and yet in some ways are very similar both of these compounds were generally less reactive toward nuclear vials then as there is and I think it's
kind of easy at least compare and added to 1 Astor we already saw this in the IRB stretching frequencies for the armored car Bonilla's lowered there's
less double bond character the nitrogen out of the animated is less Elektra negative in the oxygen of the Astor the nitrogen of the Emmitt is better able to donate and electrons by residents of the carbon he'll making it less Elektra filet and so would general principle is that Hamed's and nite trails General react less quickly and so if I tried to trying trying to epitomize where the reaction and again I'm gonna write very simple competition so I will write a set of mind but again this would be in the animated if I imagine treating it with sodium hydroxide and water like we did with our insofar pontifications how would I epitomize this I'd say a longtime were heat to make it reacts so let's say Delta lower would be how I'd describe this then again we get hydrolysis we get cleavage fiber sodium hydroxide to the carboxyl and salt in this case since we have a primary handed to ammonia I know what I mean by longtime well actually drain away which I mentioned for Esther cleavage is a good example we need hair yeah yeah you get your
drain clogged up with hair is made up of protein which a Pollyanna when I throw drying out down the drain it doesn't clog the unclogged the drain instantly the drain 0 said With their hair and the grease better down the drain for a number of hours before it unclogged 6 in the laboratory if you want speed this reaction along
you could boil your sodium hydroxide with enamored black unlike my comment about trillions of seconds for the water promoted hydrolysis of Ernesta the reaction occurs even at room temperature at a reasonable rate on the laboratory timescale and again reveals media here less reactive than Hamid's I know that that problem comes up on your on your sampling head but honestly I don't think of them personally as being very different so I can say sort of data or I take a seat overnight trails and treated under these conditions with sodium hydroxide and water may be with you for a long time in a few hours of the Indian sodium and concentrate last year I
write by by now you should be reasonably strong in your mechanistic understanding of
carboxyl compounds and maybe I'll just give you a quick quick abbreviated tour of some of the mechanisms of the new text that has them in more detail if you want but all of the principles that you can think about our similar hydroxide to reasonably good nucleophile it's it's basic can attack with kick up former territory grow intermediates and in part of his party here I really don't want to lose the forest from the trees this is the gist of this mechanism your textbook writes the next step in the mechanism has kicking out in H 2 minus I think it's OK to think about that the reality is maybe a little bit more complicated in some cases once conceived ID protonation occurring but I think I think in terms of your thinking right now it's findings to think about this anyway so that gives us the carboxyl like acid and Arab Hamied and and the and my dad and I is very basic you can think of it as pulling off a proton on the carboxyl said to give you the carboxyl late plus ammonia In 4 nite
trails and again I don't wanna get fantastically into into a whole lot of mechanism here and so maybe I'll
just sort of started selling on a mechanism there is a lot of proton shuffling that's going on but the just never left theme that I talked about in carbon nitrogen double bonds is basically in very many ways they're like carbon-oxygen double bonds and in a similar way ,comma nitrogen triple bond is very much like a carbon you were caused nitrogen double bonds and so if you look at the Oceano nite Trail you can think of it so now we're looking at the hydrolysis of nite trails you can think of this as being very similar in other words hydroxide ads we kicked in electrons you get a negative charge on nitrogen were going to shuffle some protons around now say pulsating minus stage plus another words you can think of their surprise guests I guess 1st apart on a proton years Allstate plus staged loss of course that's not plus plus that some water going ahead probe mating we can think of this as minus plus is the next step again we've got sort of a lot a lot of tedious Proton shuffling in the mechanism at this point of them abbreviated and things a little bit 1 thing to keep in mind again this theme that I mentioned where carboxyl late word nitrogen oxygen and nitrogen carbon double bonds are very similar 2 carbon and oxygen double bonds and so this structure here is really just like the analog of a carboxyl light in other words there were 2 residents structures here and again I'm kind of abbreviating abbreviating this and so we have to work equivalent president structures and end the last step you can think of is just just that we're going to pick up the all drawn explicitly it's nice to be able to pick and choose the resonance structure that you want when you're writing a mechanism installed as saying the last step here is going to be presentation In some cases you can stop United trail hydrolysis at the primary are made in other cases the animated is going to go on for further all the way to the carboxyl later just as pastors can be hired relies by 8 wickets are said to have made 2 behind realized by a quiz acid nite trails can be hired relies we assess if I take some hammered out right this is all our CEO and R 2 primer and I can't get up With acid 8 3 0 plus in water maybe he battled that and again of course you can't go to the stock and get a bottle of H 3 0 plus it's going to be sulfuric acid and water rates water yield at the carboxyl like acid and the corresponding ammonium salt so if I took the set of mind has just an example since I was using a set of mining the previous panel and I talked about trying to to stick to small molecules and let's say I cook that up with sulfuric acid and water may be a little bit he boiled it up you get the ammonium salt the ammonium in this case Vissel the interest minus the carboxyl against and this is a reaction that's done in the laboratory with proteins if you want to break down a protein into individual amino acid for example if you want to extract the amino acid Polian from here collect things and this is a procedure in organic synthesis you can take 6 smaller hydrochloric acid that's about half the strength the bottle boiled your hair
or boil your protein with it for a number of ours and it will break down to the individual amino acid so it's a very standard way to hide relies on ads and again I've just given a set of ideas and examples the keep the
structure small here do the same thing just for water comparison with this you 93 all for the sake of simplicity out just right Warwickshire here and you get the exact same products used in the corresponding acidic acid and ammonium by sulfate salt and maybe 8 since all of this is really really really analogous to Esther chemistry all the things we covered maybe I'll say right as an exercise on your own right a mechanism for let's say the acid promoted Nice real hydrolysis but but but but but but but 1 of the quick question hostile by order of the newly introduced this I want to do that yes yes yes and I was only starting us out on the nite real hydrolysis so in the cleavage of the nite trailed by sodium hydroxide to the corresponding hammered yes indeed you 1st have to the carboxyl against is the 1st step is Is the hydrolysis to the animated and that it continues on hold so and sometimes if you're careful you can control it and stopped it at the United States are right the last the last couple of minutes that I would like to take here I want to talk about a few
sympathetically useful reactions in kind of wrapped up our carboxyl against chemistry so do we haven't really talked about where acid chlorides come from and basically acid chlorides are
high in energy and so you make them from other highly reactive species acid chloride indeed member when I started out I said every member of the carboxyl like acid family can be Inter's converted by some chemistry or another and so I'm only giving you a little bit of a smattering here by making an acid chloride is a very useful reactions training carboxyl against it with biennial chloride is a great way to do it there few other species that are also used for for this but tiny of chloride SOC L 2 is particularly popular and the products of the reaction of the carboxyl like acid chloride plus if we're going to write a balanced equation the sulfur dioxide and HCl hydrogen chloride gas which generally involve allowed so I don't want go into all full detail on the mechanism and again I'll leave it to your textbook to do this but I do want to bring out at the and that highlights this chemistry so wide areas kind of a sulfur acid chloride it's kind of a double acid chloride of sulfur indeed this is very similar to another species gene which has a carbon here which also does this reaction it's a very reactive molecules extremely Elektra felt like you've got to quarantines polling electron density away from sulfur through the same types of chemistry that we still offer acid chloride reactions carboxyl like acid can react with vinyl chloride To give an intermediate that looks like a funny and hydride and this is a theme that you should pick up on in seeing the forest from the trees in this chemistry and that is that all of these species where you have a carbon meal with an ester linkage where you have a Carbondale within Esther like linkage to 1 another Elektra Feliks species that Carbondale become super Elektra fell like and nuclear files can attack even not very good nucleophile can attack at the and this seems forget the details now look at the the we'd get down chloride ready that's 1 of the by-products chloride can come in the form of money looking to enter here all intermediate and that intermediate can fall apart the kicking back kicking out sulphur-dioxide so we get arrested chloride sulfur dioxide In chloride and a new right of balance equations since a Proton was lost at the very beginning you get
HCl or that theme re-emerges in all the carboxyl against saved countless remember this is the theme of the and hydride this is the thing that we do have something electron withdrawing on the Carbondale it makes it into a good electrified and so your text gives you another reagent which in various forms and variations is quite popular before forming esters and handmade we will see it again on the very
last lecture when we talk about the chemistry of amino acids and peptides that reagent is deceased and the general idea is Hassan chlorides and asset and hydride generally species of on the way somewhere there generally things that you're making to use as terrorists and Hamed's are widely value of all important compounds the stable enough to be in drugs there the proteins and peptides in your body and the molecules that are a lot of interest and so being able to take a carboxyl like acid and alcohol can make an ass there is an extremely valuable operation being able to take a carboxyl like acid and enemy mean right it as a primary Amin although it could be a secondary meaning ammonia for that matter and make an animated that is extremely valuable operations and a reagent that often gets used for this is called DCC the variants of it but what this reagent is is dying cycle Hextall cobbled only in the car functionality but that is another member of the carbon-dioxide family of molecules and carbonic acid and carbon-dioxide are essentially like a double acid a double acid of carboxyl against its problems in the for oxidation stayed here the carbon nitrogen bonds is Electra feel like and the carboxyl like acid in the above case you can add to the carbon nitrogen bond and here's where this thing comes in so here's the cycle hexane rank this ECU cycle Hextall Carvel dynamited so we have a cycle hexane and here's the big picture here is the big idea the cargo diameter react so in exactly the same way we see final chloride it reacts to make something that looks a heck of a lot like an and hydride because remember the carbon nitrogen double bond is very similar to the carbon-oxygen double and a nucleophile can come in and just as we have seen time and time again with all the chemistry we've been seeing for the day the nuclear file can come in I'm just an abbreviated for Cycle hexane are nucleophile can come in and we can kick back and kicked out and eventually basically end up giving rise to our peaceful nucleophile are insulated nucleophile evolved in cycle but cycle Hextall urea which is a byproduct of this reaction so DCC is a very useful reagent for making esters and analysts are the last thing I wanted to book your text but has nicely kind of picked and chosen of fuel additional the reactions and I'd like to remind you of these although I know
that you also will be able to learn about them from the reading and these reactions basically fat In the broad theme that we've seen lithium aluminum hydride is a silver Super good hydride nucleophile can push hydride into practical aid in
the double or triple bond between them carbon and any sort of Elektra negative Adam 15 pressured into carbon neo-Baroque it can push it into when you mean it can push it into a nite trio lithium aluminum hydride generally reacts with completely To reduce things down and saga textbook has chosen as a couple of examples to show you in the chemistry of nite trios that lithium aluminum hydride can react with the nite at the beginning of a primary amino heading into equivalents of hydride temporarily going through an intermediate where you have aluminum on the nitrogen in your textbook has chosen to remind you and this is again just a smattering of the rich chemistry of the carboxyl like acid family much of which you are going to be guided not by having and this is where people always make a mistake learning chemistry organic chemistry not my memory because there's way too much of it but by broad principles of all the principles we've seen today you can apply to all the members of the carboxyl against his family and basically into with lots and lots of different reactions so your text but has also pointed out the reminded you that nite Friel's can reduce selectively we saw this Anastas we said lithium aluminum hydride blast after all the way down to an alcohol died ballot is a more mild reducing agent it can stop and only had 1 equivalent of hydride then so you text virtues is still to give you an example Of the died reduction of the nite trio with water is a worker for use each Rio Plus as a worker member you're going to get in mean initially but as was actually an early all and I think the gentleman in the 3rd row
there on about primary it means primary means generally are stable and break down to the corresponding how the heightened in water conditions and I'll give you a digital more examples from your textbook while we're talking about the chemistry of 90 trails and again I could show you other than many other
examples so green yard reagents and Rigano lithium reagents Alcoa prime mg X or prime held on the followed by a quiz work H 0 4 4 8 3 0 plus can add to give you the towns like so and again this is the same general idea that we've seen before the idea that these nucleophile air
In the case of the nite trio group you often can stop at 1 edition which is something you generally tend to testers anyway I think that basically wraps it up for the chapter we will
be picking up with Chapter 23 next time thank you
Single electron transfer
Chemische Bindung
Elektron <Legierung>
Fülle <Speise>
Bukett <Wein>
Funktionelle Gruppe
Aktives Zentrum
Aktivierung <Physiologie>
Setzen <Verfahrenstechnik>
Gangart <Erzlagerstätte>
Spezies <Chemie>
Schlag <Landwirtschaft>
Organische Verbindungen
Amine <primär->
Primer <Molekulargenetik>
Chemische Forschung
Chemische Forschung
Chemische Verbindungen
Chemische Struktur
Schweflige Säure
Einsames Elektronenpaar
Substrat <Boden>
Chemischer Prozess


Formale Metadaten

Titel Lecture 09. Reactions of Carboxylic Acids, Esters, Amides, & Nitriles.
Serientitel Chemistry 51C: Organic Chemistry (Spring 2012)
Teil 09
Anzahl der Teile 19
Autor Nowick, James
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DOI 10.5446/19413
Herausgeber University of California Irvine (UCI)
Erscheinungsjahr 2012
Sprache Englisch

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Fachgebiet Chemie
Abstract This is the third quarter course in the organic chemistry series. Topics covered include: Fundamental concepts relating to carbon compounds with emphasis on structural theory and the nature of chemical bonding, stereochemistry, reaction mechanisms, and spectroscopic, physical, and chemical properties of the principal classes of carbon compounds. Index of Topics: 0:56-Esters and Carboxylic Acids Reactivity 9:29-Fischer Esterification 16:41-Fischer Esterification Mechanism 29:52-Hydrolysis of Esters 32:13-Saporification 37:27-Amides and Nitriles 53:36-Making Acid Chlorides 58:11-Making Amides 1:01:33-Nitriles and LiAlH4 and other Organometallic Reagents

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